1. Technical Field
The present invention relates to an upright circuit board assembly structure and, more particularly, to an improved upright circuit board assembly structure in which at least one circuit board is soldered in a double-sided, multi-point manner to achieve strengthened physical connection and enhanced electrical connection between an electronic component and an external main printed circuit board.
2. Description of Related Art
A traditional printed circuit board (PCB) has a surface formed with specially designed electronic circuits and then mounted with different electronic components according to the circuit design, such that the functions of the electronic components can be used. The electronic components are arranged two-dimensionally on the traditional PCB and secured in position thereto by soldering the electrical soldering points of the electronic components to the PCB.
However, for certain electronic components, such as surface-mounted photo interrupters and side view LEDs, it is required that the PCB be fixed vertically on the assembly surface of an external device. Hence, an upright circuit board assembly structure has been successfully developed and is now in use.
Please refer to FIG. 1 and FIG. 2 for a partial side view and a perspective view of a conventional upright circuit board assembly structure, respectively. The conventional upright circuit board assembly structure includes an electronic component 2′ and two circuit boards 5′.
The electronic component 2′ has a coupling portion 21′. The coupling portion 21′ has a first outer surface 211′ and a second outer surface 212′.
Each circuit board 5′ has a first surface 53′ coupled to the first outer surface 211′ or the second outer surface 212′ of the coupling portion 21′. Since the first outer surface 211′ and the second outer surface 212′ are vertically extending surfaces, the circuit boards 5′ are coupled respectively to the first outer surface 211′ and the second outer surface 212′ by means of a bonding substance. In addition, each circuit board 5′ includes two first electrical connection portions 51′. The first electrical connection portions 51′ are made of an electrically conductive metal and provided on a second surface 54′ of each circuit board 5′. The first electrical connection portions 51′ are soldered to an external device 3′ via a solder paste 4′ (tin solder). Thus, by soldering the circuit boards 5′ to the external device 3′ in a single-sided, two-point manner, the electronic component 2′ is mounted on the external device 3′. The physical connection between the first electrical connection portions 51′ and the external device 3′ also maintains electrical connection between the electronic component 2′ and the external device 3′ such that electrical functions of the electronic component 2′ can be used.
As shown in FIG. 2, while each of the circuit boards 5′ is coupled to the external device 3′ by soldering the two first electrical connection portions 51′ on the second surface 54′ to the external device 3′, the soldering is performed only in a single-sided manner. Therefore, when the electronic component 2′, such as a side view LED, having the conventional upright circuit board assembly structure is applied to a large outdoor LED bulletin board, solder joints between the first electrical connection portions 51′ and the external device 3′ are constantly subject to day/night temperature differences and moisture, which may cause the solder paste 4′ to fall off gradually. When the electronic component 2′, such as a side view LED, having the conventional upright circuit board assembly structure is applied to the backlight module of the LCD screen of a laptop computer or to the outer screen/backlight module of a cell phone, the shock and external force experienced by the laptop computer or cell phone while being carried around tend to affect the conventional upright circuit board assembly structure on a long-term basis. Consequently, the solder paste 4′ used for the single-sided soldering may fall off, thus impairing the electrical connection between the electronic component 2′ and the external device 3′. Even more seriously, the electronic component 2′ itself may fall off from the external device 3′, such that the electronic component 2′ can no longer be used.
Besides, in the case where the electronic component 2′ is a side view LED and applied to a large outdoor LED bulletin board, if the solder paste 4′ gradually falls off due to the fact that the solder joints between the first electrical connection portions 51′ and the external device 3′ are subject to long-term day/night temperature differences and moisture, the malfunctioning electronic component 2′ cannot be replaced or be repaired by re-soldering until the entire LED bulletin board is disassembled for maintenance. Such maintenance, however, is time-consuming, labor-intensive, and therefore undesirable.
Therefore, in view of the various shortcomings of the conventional upright circuit board assembly structure, the inventor of the present invention conducted extensive research and finally succeeded in developing an improved upright circuit board assembly structure as disclosed herein.